JPH0936282A - Semiconductor device - Google Patents

Abstract

(57) Abstract: An epoxy resin, a curing agent and an inorganic filler are contained, the content of the inorganic filler is 60% by weight or more of the entire composition, and the viscosity at the molding temperature is 50 poise or less. 2. A semiconductor device characterized by being transfer-molded and sealed with a liquid or paste epoxy resin composition at room temperature substantially free of gelling residue on a 50-mesh sieve. According to the semiconductor device of the present invention, by transfer molding and sealing using an epoxy resin composition which is liquid or paste at room temperature and substantially does not contain gelling residue having a specific particle size or more, It is possible to obtain a highly reliable semiconductor device that is free from deformation of the gold wire during molding, unfilled defects, and void defects.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin-encapsulated semiconductor device, and in particular, it is encapsulated with an epoxy resin composition which is liquid or paste at room temperature and substantially free of gelling residue having a specific particle size or more, The present invention relates to a highly reliable semiconductor device that is free from deformation of a gold wire during molding, unfilled defects, and void defects.

[0002]

2. Description of the Related Art Recently, the problems to be solved by the invention
Semiconductor packages are large, multi-pin, and thin, and there are no problems such as unfilled defects, void defects, and gold wire flow even if they are encapsulated with an epoxy resin composition for encapsulation, which has never been a problem in the past. Is becoming a problem.

That is, conventionally, for semiconductor devices, a powdery epoxy resin composition which is solid at room temperature is used, and after tableting this, transfer molding is carried out at a temperature of around 170 ° C. under a pressure of about 70 kg / cm ^2. It was sealed by. In this case, this type of solid epoxy resin composition,
Since it is produced by a two-roll machine heated with a curing catalyst and a continuous extruder, it contains a trace amount of gelling residue. This gelling residue blocks the gate opening and causes unfilling, or the lead pitch becomes very narrow in a multi-pin package, so the gelling residue is pinched between the leads, causing voids and lead deformation. In addition, it is said that the gelled residue collides with the gold wire during molding, causing deformation of the gold wire. Further, in molding, the tableted solid resin composition is heated and molded under high pressure in a short time so that the temperature does not become constant inside the tablet, and voids are generated because the viscosity is nonuniform. Frequent defects such as a gold wire flow in which the gold wire flows in the resin flow direction occur. In order to improve this kind of defect, the melt viscosity at the molding temperature of the resin composition may be made as low as possible, but on the contrary, since it is essential that these compositions are solid powder at room temperature, the melt viscosity is extremely high. If the composition is very low, there is a problem in that it is too soft to be made into a solid powder during production. Therefore, until now, transfer molding of semiconductor devices has not been performed at all using a resin composition having a very low viscosity.

On the other hand, sealing with an epoxy resin composition which is liquid at room temperature is also performed by a potting method, a coating method, etc. However, it is used in a limited field because of poor productivity and insufficient reliability. The reality is that it is used only for devices.

The present invention has been made in view of the above circumstances, and gold at the time of molding is sealed with an epoxy resin composition which is liquid or paste at room temperature and substantially free of gelling residue having a specific particle size or more. An object of the present invention is to provide a highly reliable semiconductor device free from line deformation, non-filling defects, and void defects.

[0006]

Means for Solving the Problems and Modes for Carrying Out the Invention In order to achieve the above object, the present inventor has found that the size of the gelling residue of the epoxy resin composition and the deformation or non-existence of the gold wire due to gate clogging or the like. As a result of intensive studies on the relationship between molding defects such as defective filling and void defects, the relationship between the viscosity of the resin composition at the time of molding, and the cause of defective leading edge packages, a gel of epoxy resin composition of 50 mesh or more was obtained. There is a good correlation between the number of oxidization residues and unfilled defects, and further, a low viscosity of 50 poise or less at the time of molding causes deformation of the gold wire during molding and unfilled defects. It was found that it is a necessary and sufficient condition for obtaining a highly reliable semiconductor device without void defects.

That is, by using an epoxy resin composition which is liquid or pasty at room temperature as a sealing material, each component can be sufficiently mixed and dispersed even after the curing catalyst is added, and gelation of 50 mesh or more is achieved. Since the residue can be substantially free of impurities, the gelled residue blocks the gate opening, resulting in unfilling failure, or the gelled residue is pinched between the leads, causing voids and lead deformation. It is possible to effectively suppress the occurrence of a cause or the deformation of the gold wire due to collision with the gold wire during molding. Moreover, by making the melt viscosity of the resin composition at the molding temperature as low as possible, the resin composition can be pressure-injected into the cavity at a low pressure during transfer molding, and the pressure can be increased after the injection is completed. Since the method can be adopted, it has been found that a good and highly reliable semiconductor device free from air entrainment and gold wire deformation (gold wire flow) can be obtained, and the present invention has been completed. .

Therefore, the present invention contains an epoxy resin, a curing agent and an inorganic filler, and the content of the inorganic filler is 60% by weight or more of the whole epoxy resin composition, and
A semiconductor characterized in that it has a viscosity at a molding temperature of 50 poise or less and is transfer molded with a liquid or paste-like epoxy resin composition at room temperature on a 50-mesh sieve and substantially free of gelling residue, and sealed. Provide a device.

Hereinafter, the present invention will be described in more detail.

The semiconductor device of the present invention has a low viscosity and is transfer-molded and sealed with a liquid or pasty epoxy resin composition at room temperature containing substantially no gelling residue having a specific particle size or more. is there. In this case, the epoxy resin composition contains (A) epoxy resin, (B) curing agent, and (C) inorganic filler.

Here, the epoxy resin as the component (A) has two or more epoxy groups in one molecule and has a room temperature (2
Any epoxy resin that is liquid or pasty at 5 ° C. can be used, and as this type of epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, or the following structure which has been conventionally known is used. An epoxy resin represented by the formula and the like can be mentioned.

[0012]

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Further, an epoxy resin having two or more epoxy groups in one molecule and solid at room temperature, such as phenol novolac type epoxy resin, cresol novolac type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, cyclopentadiene. It is also possible to mix one or two or more types of epoxy resin and the like with the liquid or pasty epoxy resin at room temperature described above.

In order to use these epoxy resins in semiconductor encapsulants, which are required to have high reliability, the content of hydrolyzable chlorine is 1000 ppm or less, more preferably 800 ppm or less. It is recommended to use those having chlorine ions or sodium ions extracted at a temperature of 120 ° C. of 10 ppm or less, more preferably 5 ppm or less.

As the curing agent as the component (B), a phenol resin containing two or more phenolic hydroxyl groups in one molecule is preferable, and particularly a phenol novolac resin, a cresol novolac resin, a phenol aralkyl resin, a naphthalene type phenol resin, Examples include cyclopentadiene type phenolic resins and those containing a phenolic hydroxyl group represented by the following structural formula.

[0016]

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Here, since the above-mentioned phenol resin needs to be in a liquid or paste state in a state of being mixed with a liquid epoxy resin, it is a binuclear compound (that is, a phenol resin containing two aromatic rings in the molecule) in the entire molecular weight distribution. ) Is 50% (wt%, the same applies below) or more, and the proportion of 5 or more nuclides is 10% or less, more preferably 70% or more of 2 nuclei and 5 of 5 nuclides.
% Or less is preferable. Further, it is more preferable that the ratio of free phenol is 0.5% or less and the total ratio of the binuclear body and the trinuclear body is 95% or more.

The phenol resin, like the epoxy resin as the component (A), is preferably 10 ppm or less, and particularly preferably 5 ppm or less in terms of chlorine ion and sodium ion extracted at a temperature of 120 ° C.

Further, in the resin composition of the present invention, as a curing agent, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride,
An acid anhydride such as methylhymic acid anhydride may be used alone, preferably in a mixture with the above-mentioned phenol resin.
Further, imidazole derivatives such as 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole and amine compounds can also be used. Further, conventionally known dicyandiamide can also be used as a curing agent. In this case, since dicyandiamide has a high melting point, it is necessary to use a pulverizer at 15
It is preferable to use it by making it finer than 0 mesh, particularly finer than 200 mesh. Alternatively, it is preferable to knead dicyandiamide finely pulverized with an epoxy resin or a silicone-modified resin in advance with a three-roll mill or the like before use.

The amount of the curing agent used is a curing effective amount. When a phenol resin is used as the curing agent, the phenolic hydroxyl group is preferably 0.5 to 1 with respect to 1 mol of the epoxy group of the epoxy resin as the component (A). 0.6 mol, more preferably 0.8 to 1.4 mol. If it is less than 0.5 mol, the phenolic hydroxyl group will be insufficient, and the proportion of homopolymerization of the epoxy group will increase, and the glass transition temperature may decrease. On the other hand, if it exceeds 1.6 mol, the proportion of phenolic hydroxyl group will be high. In addition to the decrease in reactivity, the crosslink density is low and sufficient strength may not be obtained.

The resin composition of the present invention may optionally contain a curing accelerator, and phosphorus-based compounds, imidazole derivatives, cycloamidine-based derivatives and the like may be used as the curing accelerator. . The compounding amount of the curing accelerator is preferably 0.01 to 10 parts by weight, particularly 0.1 to 5 parts by weight, based on 100 parts by weight of the total amount of the epoxy resin and the curing agent.

The composition of the present invention contains various conventionally known inorganic fillers as the component (C) in order to reduce the expansion coefficient and improve the thermal conductivity. In this case, the inorganic filler can be appropriately selected depending on the application of the epoxy resin composition, for example, crystalline silica, fused silica, alumina, silicon nitride, aluminum nitride, boron nitride, magnesia, calcium silicate, Gold powder, silver powder, aluminum powder, copper powder, nickel powder and the like are used. When the semiconductor element is an element that generates a large amount of heat, it is preferable to use alumina, boron nitride, aluminum nitride, silicon nitride, or the like, which has a high thermal conductivity and a low expansion coefficient, as a filler. Further, it may be used by blending with fused silica or the like.

The shape of the powder of the above-mentioned inorganic filler is not particularly limited, and any of crushed angular particles, spherical particles, scaly particles, and the like can be used depending on the application. Moreover, you may mix and use each. Further, ultrafine silica such as Aerogel may be added for imparting thixotropic properties.

Regarding the particle size distribution of these inorganic fillers, the maximum particle size is 74 microns or less, especially 50 microns or less,
Those having an average particle size of 2 to 30 microns, particularly 3 to 20 microns are preferred. When the maximum particle size is larger than 74 microns, it is difficult to fill the minute voids, and when using a dispenser, there is a possibility that the tip of a fine needle may be blocked. If the average particle size is less than 2 microns, the particle size becomes too fine and the viscosity becomes high, so that a large amount cannot be filled.
If it is larger than micron, the coarse grain size increases, which may cause the gate clogging. Further, it is preferable to use those fillers which have been surface-treated with a silane coupling agent or a titanium coupling agent in advance.

The content of the inorganic filler is 60% by weight or more, preferably 60 to 95% by weight, more preferably 70 to 90% by weight, based on the whole composition, and if the content is less than 60% by weight. The expansion coefficient of the cured product becomes large, resulting in poor thermal shock resistance such as package cracks and chip cracks occurring in temperature cycle tests. In this case, the inorganic filler is usually added in an amount of 150 to 1000 parts by weight, particularly 250 to 900 parts by weight, based on 100 parts by weight of the total amount of the epoxy resin and the curing agent. If it is less than 150 parts by weight, the expansion coefficient cannot be lowered sufficiently, while 10
If the amount is more than 00 parts by weight, the viscosity may be too high and molding may not be possible.

Further, it is possible to add an organic resin powder such as polystyrene or silicone in addition to the inorganic filler. In this case, the particle size and shape of the organic resin powder can be the same as those of the inorganic filler.

Further, the epoxy resin composition of the present invention contains
If necessary, a silicone-modified resin, which is a copolymer of an organohydrogenpolysiloxane and an alkenyl group-containing phenol resin or an alkenyl group-containing epoxy resin, can be blended for the purpose of improving stress characteristics. In this case, the above silicone-modified resin is already known (Japanese Patent Publication Nos. 63-60069 and 63-60070), and stress can be obtained by appropriately changing the structure of the epoxy resin part and the structure of the silicone part according to the purpose. A copolymer having good properties and an optimum structure can be obtained, and such a known copolymer can be used.

As the silicone-modified resin, for example, the alkenyl group of an alkenyl group-containing epoxy resin or an alkenyl group-containing phenol resin and the number of silicon atoms in one molecule represented by the following average composition formula (1) are 200 to 4
And a copolymer obtained by an addition reaction of the organohydrogenpolysiloxane having 1 to 5 SiH groups with SiH groups.

H_aR¹ _bSiO_{{4- (a + b)} / 2} ... (1) (However, in the formula, R¹ Represents a substituted or unsubstituted monovalent hydrocarbon group.
A, b are 0.002 ≦ a ≦ 0.1, 1.8 ≦ b ≦
2.2, 1.8 <a + b ≦ 2.3
You. ) Alkenyl group-containing phenol used in this copolymer
As the resin or the alkenyl group-containing epoxy resin,
Those represented by the following formula are preferable.

[0030]

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[0031]

Embedded image (P and q are usually 1 ≦ p ≦ 20, preferably 1 ≦ p ≦ 1
It is a number represented by 0, 1 ≦ q ≦ 5, and preferably 1 ≦ q ≦ 3. )

On the other hand, the organohydrogen of the above formula (1)
In the polysiloxane, R¹ Usually has 1 to 1 carbon atoms
12, especially 1 to 10 carbon atoms, preferably aliphatically unsaturated
A substituted or unsubstituted monovalent hydrocarbon group excluding bonds
, For example, methyl group, ethyl group, propyl group, butyl
Alkyl such as a group, 2-ethylbutyl group and octyl group
Alkenyl such as a group, vinyl group, allyl group, hexenyl group
Group, cyclohexyl group, cyclopentyl group, etc.
Aryl group such as alkyl group, phenyl group, tolyl group,
Aralkyl groups such as jyl group and phenylethyl group;
Some or all of the hydrogen atoms bonded to the carbon atoms of the group are halo.
Substituted by a gen atom or a cyano group, such as chloro
Romethyl group, bromoethyl group, trifluoropropyl
Group, cyanoethyl group and the like. Also, a and b are
0.002 ≦ a ≦ 0.1, preferably 0.01
≦ a ≦ 0.05, 1.8 ≦ b ≦ 2.2, preferably 1.
8 ≦ b ≦ 2.0, 1.8 <a + b ≦ 2.3, preferably
Is a number in the range of 1.81 ≦ a + b ≦ 2.1.

The number of silicon atoms in one molecule of the organohydrogenpolysiloxane is 20 to 400,
It is particularly preferably 40 to 200, and particularly preferably 80 to 150. If it is less than 20, this silicone-modified resin will dissolve in the epoxy resin, making it impossible to take a fine sea-island structure with the epoxy resin as a matrix,
As a result, sufficient impact resistance may not be obtained, and low stress may be lacked. If it exceeds 400, the silicone-modified resin is phase-separated from the epoxy resin and the strength of the cured product becomes weak. In some cases, when the composition obtained has thixotropic properties and fluidity is required, there may be a problem.

It is preferable that the organohydrogenpolysiloxane is basically linear, but it may have a partially branched structure.

Typical examples of the silicone-modified resin used in the present invention include those represented by the following structural formula.

[0036]

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[0037]

[Chemical 6]

The compounding amount of this silicone-modified resin is 1 total amount of the silicone-modified resin, the epoxy resin, and the curing agent.
The amount of the organopolysiloxane in the silicone-modified resin (for example, the above-mentioned copolymer) is not more than 20 parts by weight, for example, 0 to 20 parts by weight, preferably 0.5 to 20 parts by weight, and particularly, to 100 parts by weight. It can be 1 to 10 parts by weight. If the amount is less than 0.5 parts by weight, sufficient low stress may not be imparted, and if the amount is more than 20 parts by weight, low stress may be imparted, but the viscosity becomes extremely high and the workability deteriorates, and the strength is weak. There may be a drawback that

For the purpose of decreasing the viscosity, the composition of the present invention contains n-butyl glycidyl ether, phenyl glycidyl ether, styrene oxide, t-butyl phenyl glycidyl ether, dicyclopentadiene diepoxide, 1 Diluents such as 4,4-diglycidoxybutane and 1,6-diglycidoxyhexane can be added. Also, if necessary,
Various additives can be blended depending on the application. For example, a silane coupling agent, a titanium-based coupling agent, a coupling agent such as an aluminum-based coupling agent, a coloring agent such as carbon black, a nonionic surfactant, a fluorine-based surfactant, a wetting improver such as silicone oil, or the like. An antifoaming agent or the like can be added depending on the case.

The epoxy resin composition prepared by mixing and kneading the above-mentioned various materials is liquid or paste at room temperature.
In particular, the viscosity at room temperature (25 ° C.) is 100 poises or more and 50,000 poises or less, and the molding temperature (usually 16
The viscosity at 0 to 180 ° C.) is preferably 50 poise or less, and particularly preferably 40 poise or less. Viscosity at molding temperature is 5
If it is higher than 0 poise, defects such as deformation of die pads and leads, pinholes, etc. will occur when a package having a number of pins exceeding 200 pins and a thickness of 1 mm or less is sealed with the resin composition.

The method for producing the composition of the present invention is not particularly limited, and a known production method can be employed. For example, an epoxy resin and a curing agent may be simultaneously or separately added with heat treatment if necessary. The desired epoxy resin composition can be obtained by stirring, dissolving, mixing and dispersing, and adding an inorganic filler to this mixture and mixing, stirring and dispersing. Here, when the respective components are blended, the resin components such as the epoxy resin and the curing agent in the composition are usually filtered at a room temperature and, if necessary, under heating at about 150 ° C. or less through a 50 mesh screen. It is preferable to blend the above-mentioned products, and by performing such pretreatment, it is possible to effectively eliminate gel-like substances that may be mixed in the raw material components. In the same sense, it is desirable to use the silicone-modified resin as an optional component, which is usually filtered through a 50-mesh screen under heating at about 150 ° C. or lower. At this time, devices for mixing, stirring, dispersing, etc. are not particularly limited, and a reiki machine equipped with a stirring, heating device, a three-roll, a ball mill, a planetary mixer, etc. can be used, and these devices are used in appropriate combination. You may.

In this manufacturing process, since the resin composition of the present invention is liquid at room temperature, it can be mixed and dispersed at a low temperature even after the addition of the curing catalyst as compared with the case of the conventional solid resin composition. . Therefore, in addition to the gelled substance existing in each raw material component before compounding, the gelling residue generated in the manufacturing process, which is a problem in the conventional resin composition, in particular, particles of 50 mesh or more that cause unfilling failure are substantially formed. In addition, it is possible to eliminate the above, and it is possible to manufacture a highly reliable semiconductor device.

Further, as a method of transfer molding these liquid epoxy resin compositions at room temperature or in paste form, the epoxy resin composition is used in a cup described in USP (US Pat. No. 5,098,626). Can be poured into the pot and sealed in a vacuum, and can be molded using an ordinary molding device.

In this case, as molding conditions, since the epoxy resin composition in the cup is already liquid or paste at room temperature, the transfer pressure is in a low pressure state at the initial stage of pressurization, preferably 10 to 40 kg / cm ² . A good molded product can be obtained by injecting the resin into the cavity under pressure and, after the injection is completed, increasing the pressure to preferably 50 to 80 kg / cm ² . Specifically, FIG. 1 shows a pressure profile at the time of molding using the epoxy resin composition of the present invention. When the epoxy resin composition of the present invention is molded under the conditions for molding a conventional solid epoxy resin composition,
Since the molding is carried out at a pressure of about 70 to 100 kg / cm ² from the beginning, the pressure is rapidly transmitted to the epoxy resin composition of the present invention and flows into the cavity at a high speed from the gate. Cause deformation.

[0045]

According to the semiconductor device of the present invention, transfer molding is performed by using an epoxy resin composition which is liquid or paste at room temperature and substantially free of gelling residue having a specific particle size or more. As a result, it is possible to obtain a highly reliable semiconductor device that is free from deformation of the gold wire during molding, unfilled defects, and void defects.

[0046]

EXAMPLES The present invention will now be described specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[Examples and Comparative Examples] Epoxy resin compositions (No.
1 to 5, 7) and a conventional solid powdered epoxy resin composition (No. 6) at room temperature. The composition N
o. In Nos. 1, 2 and 4 to 7, the epoxy resin component, the phenol resin component and the silicone-modified epoxy resin component were blended in such a manner that they were pressure-filtered with a 50 mesh screen at room temperature (25 ° C) or under heating. Composition No. In No. 3, the components not subjected to this filtration treatment were blended. Physical properties of the obtained epoxy resin composition were measured by the following methods. The results are also shown in Table 1. Viscosity measurement A Koka type flow tester was used, and measurement was performed at 175 ° C. using a 0.5 mmφ die. The resin composition was placed on a hot plate having a gelation time of 175 ° C., and the time until the fluidity disappeared was measured while stirring with a spatula. After pouring it into a mold with a glass transition temperature and expansion coefficient of 4 × 4 × 15 mm, defoaming it, and using a test piece that was heat-cured at 120 ° C. for 1 hour and 175 ° C. for 2 hours, each time with a dilatometer. Minute 5
It was measured by raising the temperature at ° C. The expansion coefficient is a value below the glass transition temperature. Mechanical strength (bending strength, bending elastic modulus) A test piece that was made by pouring resin into a mold with a size of 10 × 100 × 4 mm, defoaming it, and then heat curing at 120 ° C. for 1 hour and 175 ° C. for 2 hours. Was measured according to JSK6911. 100 g of the gelling residue epoxy resin composition is weighed and added with acetone 30
After completely dissolving it in 0 ml, it was poured onto a 50-mesh sieve, and the number of gelling residues remaining on the sieve was counted under a microscope.

[0048]

[Table 1]

[0049]

[Chemical 7]

[0050]

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Next, each epoxy resin composition shown in Table 1 was poured into the cup described in the above-mentioned USP (US Pat. No. 5,098,626), and after sealing, a multi-plunger type transfer molding machine was used. Used, 208 pin,
Pad size 10x10mm, chip size 8x8, wire length (longest) 3mm, package size 24x24
mm, thickness 1.4 mm TQFP package at 175 ° C
At the temperature of 200, 200 pieces were sealed each. No. For 1 to 5 and 7, the initial injection pressure was set to 20 kg / cm ² , and after the resin was completely injected into the cavity, it was pressurized to 70 kg / cm ² and molded. On the other hand, No. 6 is 70k from the beginning of molding as usual
It was molded at a pressure of g / cm ² . The number of unfilled defects in 200 sealed packages and the defective wire flow of the packages were examined using soft X-rays. Further, the deformation of the die pad was investigated using an ultrasonic flaw detector. Regarding the wire flow, the 10 longest wires were examined, and those having a deformation of 10% or more were regarded as defective, and the number of the packages was measured. Table 2 shows the results.

[0052]

[Table 2] From the results shown in Table 2, the epoxy resin composition of the present invention which is liquid or pasty at room temperature and contains substantially no gelling residue on 50 mesh, even in a package which is very difficult to mold, It was confirmed that the molded / encapsulated product could provide a good semiconductor device without any unfilling failure, wire flow, or die pad deformation.

[Brief description of drawings]

FIG. 1 is a graph showing a pressure profile during transfer molding of the epoxy resin composition of the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeki Ino 1 Hitomi, Osamu, Matsuida-cho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (72) Innovator, Nobuhiro Ichi Matsui, Usui-gun, Gunma Prefecture Tamachi Daiji Hitomi 1-10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Technology Laboratory

Claims (2)

[Claims] 1. An epoxy resin, a curing agent, and an inorganic filler are contained, the content of the inorganic filler is 60% by weight or more of the entire composition, and the viscosity at the molding temperature is 50 poise or less and 50 mesh. A semiconductor device characterized by being transfer-molded and sealed with a liquid or paste-like epoxy resin composition at room temperature containing substantially no gelling residue on a sieve. 2. The semiconductor device according to claim 1, wherein a silicone-modified resin is blended with the epoxy resin composition.